Railway-traffic-controlling apparatus



Oct. 5 1926. 1,602,137

H. A. WALLACE RAILWAY TRAFFIC CONTROLLING APPARATUS v Filed August 6,1923 2 Sheets-Sheet -1 INVENTOR I M1, ATTORNEY H. A. WALLACE RAILWAY TRAFFIC CONTROLLING APPARATUS Filed August 6} 192,3 2 Snets-Shet 2 U r w; 1% 6 INVENTOR I H 1 4 M ATTORNEY Patented Get. 5, 1926.

UNETEE STATtZfi ha -limit? HERBERT A. 'W'ALLACE, OF EDGEl/VOOD BOROUGH, PENNSYLVANIA, ASSIGNOR TO THE UNION SVJITCH & SIGNAL COIVIPANY, OF S /VISSVALE, PENNSYLVANIA, A CORPORA- TION OF PENNSYLVANIA.

RAILWAY-TRAFFIC-CONTROLLING APEARATUS.

Application filed. August 6, 1923. Serial No. 655,927.

My invention relates to railway trafiic controlling apparatus, and particularly to apparatus of the type comprising train carried governing mechanism controlled by energy received from the trackway. More particularly, my invention relates to the traclrway portion of such apparatus.

I will describe one form of railway traffie controlling apparatus embodying my invention, and will then point out the novel features thereof in claims.

In the accompanying drawings, Figs. 1 and 1 when placed end to end in the order named form a diagrammatic view showing one form and arrangement of railway tratiic controlling apparatus embodying my invention.

Similar reference characters refer to similar parts in each of the figures.

Referring to the drawings, the reference characters 1 and 1 designate the track rails of a single track railway over which traffie normally moves in both directions, the portion of track shown in the drawing being provided with two passing sidings F and F. For purposes of convenience of description I shall hereinafter term that portion of track which lies between the two aassing sidings F and F, a stretch of single track, it being understood that by combining the required number of such stretches with the required number of interposed passing sidings F, F etc., a complete sys-v tem f any desired length may be constructed. The track rails 1 and 1 of the stretch shown in the drawings are divided, by means of insulated joints 2 into three consecutive track sections AB, B-C 'and C-D, it being understood however that any reasonable number of such sections may occur in a. single stretch. The main track parallel with the siding F is also provided with a track section DE.

Tratlic from left to right over the stretch of track shown in the drawing is controlled by three roadside signals S, S and S which are located at points A, D and E, re ely. In similar fashion traffic from right to left over this track is controlled by three other signals 8", S and S located at points E, D and A, respectively. In other words, va pair of opposing signals is located at each end of each passing siding.

As shown in the drawings, each of the signals S S, S S S and S is a colored light signal, and each is provided with three signal lamps 4c, 5 and 6, adapted to project, when energized, a beam of red light,yellow light, or green light, respectively, and thus display a, stop, caution or proceed indieation in accordance with common practice. I

Each end of each track section is provided with a source of track circuit current such as the secondary 7 of a track transformer designated by the reference character T with a suitable exponent. Each such transformer secondary is constantly connected with the track rails of its associated section, and the primary 8 of suchtransformer is at times supplied with alternating current by means which will be described in detail hereinafter. Interposedbetween one track rail 1 and the seconcary winding 7 of each transformer T is an impedance 9, one function of which is to limit the outputof the transformer when its terminals are short circuited by the wheels and axles of a passing train.

Each section is provided withtwo track relays, one located at each end of the section, andeach of which relays is designated by the reference character it with a suit able exponent. Each such relay comprises a track winding 15 and a second winding 10 which is constantly supplied with alternat ing current from a suitable source. For example, referring particularly to relay R winding 10 is provided with a circuit which passes from the secondary of line transformer H through w1re 11, windlng 10 of relay PF, and wires 12, 13 and .14 back totransformer H The primary of line transformer H is constantly supplied with alternating current from a generator 0 over line wires 3 and 3*. A similar line transformer is located adjacent the juncture of each'two track sections and is designated by the reference character H with an exponent corre sponding to the location.

Associated with each track relay R is a line relay designated by the reference character W with the same exponent as that which is applied to the corresponding track relay. Referring particularly to line relay V1 this relay is provided with a circuit which passes from the secondary of line transformer H through wires 11 and .16,

front contact 17 of relay wires 18 and 19, front contact 20 of track relay R wire 21, back contact 22 of a stick relay K wire 23, front contact 2% of relay R wire 25, winding'of relay W, and wires 26, 27, 28, 29 and 14 back to transformer H It is plain that this circuit is closed only when relays W and R are energized and auxiliary relay K is de-energized. The circuit just tr ced is provided with a branch which passes from wire 11, through wire 30, front contact-31 of auxiliary relay K and wire 32 to wire 19. It follows that when relay K is energized the closing of its front contact 31 removes the relay W from the control of relay W The control of relay l i is exactly similar to that of relay i3 Relay W is controlled by track relays audit for section C D, and relay TV" is-controlled by track relays Rand R for section Al3, there being-no line relay'contacts intlie circuits for these relays, and consequently no stick relays associated with. suchcircuits.

Relays W QlV, V W l 1 and are of the polarized three posit-ion typeand are each provided with two windings 33 and 3.4,one of which 33 is constantly connected with a source of alternating current. Be ferring' particularly to relay 3V vind 33 of this relay is provided with a circuit which passes from transformer ll through wires 39 and 38, winding of relay W and wires 37, 36 and '35 loack to transformer H The relay is-arranged .to be responsive to reversals of the relative polarity of the current supplied to winding 34 which is provided with a circuit passing from the secondary of an auxiliary transformer lif whose primary is constantly supplied with alternating current over wires 14 and 11 from transformer H The circuit for winding 34 .is from the secondary of transformer M through wire 40, front contact 41 of relay wire 42, frontcontact of relay 74, wire 414i, back contact 4 5 of auxiliary relay K wire 46, front contact 411'? of track relay R wire 48, front contact 49 of track relay di wire 50, windinp; 34: of relay V3 wires 3'? 36 51 and 52 front contact 53 of relay 1V and wire 54 back to trans former M This circuit is closed only when relays B B v and W are energized relay K is de energized under which conditions the polarity of the currentsupplied to relay is what I shall term normal relative polarity, and the contact fingers on relay W are swung to the right. l Vhen relay V1 is .de-energized, however, as by a train moving from right to left in section JB-C, relay K as will appear hereinafter, is energized and the CllCUlt for windin 1 f0 13 h of relay l l then passes from transiormer M9, through wire 40, \back contact 53 of relay W w1res'5z2, 51, 36 and 37, winding 3 of relay V1 wire 50, front contact 49 of track relay R wire 48, front contact 47 of relay R wire 46, front contact of relay K wires 55 and 56, back contact 421 of relay Vi andwire 54 back to transformer M inis circuit is closed only when r ys R R and K areenergized-and relay J is deenergized, under which conditions relay 3V is supplied with'current of what I shall term reverse relative polarity and the con tact fingers on this relay will be swung toward the left. Line relay W located at point A and line relay l l located at point E are controlled by circuits similar to those just traced for line relay W Associated with each-of the line relays VJ lV V7 V7 Vi -and W isa repeater relay designated by the reference character G with an exponent corresponding to the location. Each of the repeater relays G controlled by its associated line relay follows: Referring for exan'iple to repeater relay G located point I), this reh provided with a circuit which passes irom transformer l P, whose primary is constantly supplied with alternating current from transformer H through wire 57,, normal or reverse contact of relay ll, winding of relay G wires andiiS, bacl: contact 61 of track relay R and wires GQandback to transformer L3. This circuit is closed only when 'rclay -E is cleeenergjized but it will be noticed that back contact 67 of track relay 3 is connected in multiple with back contact 61 of track relay R and that the oil cuit will therefore be closed by de-energiaa-- tion of relay R Each of the remaining; rapeater relays is provided with a circuit similar to that just'traced for relay In addition, .one terminal of each of :the relays G GQG and G is connected'to a'con'n'non wire 65. Similarly, relays G and G are connected by means of wire witli' two relaysiat .the left hand end of siding and not shown in the drawing, The resultof suclrconnection is that relays G G G and G are normally deenergized but that when a train enters section Cl), DE, r theisection to the right of EA these relays will be immediately energized, provided the associated relays l t energized. The o eration of the repeater relays associated former M through wire 80, front contact 77 of of 73 of 9 of relay G, wire 78, front contact track relay lt wire 76, iront contact track relay R", wire 74's, hack contact relay K wire T2, front Contact *"l of track relay R wire 70, Winding-34: of relay W wires 63 and '83, front contact 81 of relay'G,

ill)

and wire 82 back to secondary of trans former M .Vhen relay G is de-energized current of the other relative polarity is supplied to relay 1V over a circuit passing from transformer M through wire 80, back contact 81 of relay G wires 83 and 63, through winding 3 1- of relay -W as oefore to wire 78, back contact 79 of relay G and wire 82 back to transformer M it is therefore clear that, assuming relay K to be (lo-energized and relay R, PR, R to be energized, relay 1V is energized in one direction or the. other depending upon the condition of energization of relay G. Line relays V7 and W are provided with circuits similar in all respects to those just traced for line relay W The auxiliary or stick relay K associated with track relay R is provided with a pickup circuit which passes fron'i transformer H through wires 11 and 84:, back contact of relay VJ, vire 86, back contact 8'7 of track relay R wire 88, back contact or track relay R wire 90, front contact 91 relay ll, wire 02, winding of relay K and wires 93, 9st, and 1% back to transformer E The stick relay K vill be energized therefore as a train, moving from right to left, enters section BC at point C. The energizing of this relay closes a retaining or stick circuit which passes from transformer H through wires 11 and 95, back contact of relay R wire 97, front contact 98 of relay K wire 90, winding of relay K and thence to wire 03 and back to transformer H as before, This retaining circuit is closed only when relay K is energized and relay R is de-energized, and serves to maintain K in its energized condition as long as any part of section BC is occupied by a train. Stick relays K, K and K are conroll-ed over circuits similar to those just described for relay K Auxiliary relay K" is provided with a pick-up circuit which passes from transformer F through wires o5 96, back contact 97 of track relay It wires 98 and 99, front contact 100 of reoeater relay '31", wire 101, winding of relay K and wires 102, 103 and 10 1 back to transformer H This relay is also provided with a retaining or stick circuit which commences at wire 98 and leads through wire 107, front contact 106 of relay 11, and wire 105, back to the winding of relay K It follows that the relay is normally ale-energized, but is closed by the entrance into section D-E of a train moving from right to left, and remains closed as long as the train occupies such section. A stick relay K is controlled by circuits similar in all respects to these just traced for relay K.

Relay P serves as a repeater for relay K and is controlled over a circuit which commences at transformer H, and leads w' as 108 and 109, front contact 110 wire 111, back contact 24 of wire 28, back contact wire 21, back contact 20 of relay 112, windingof relay P and wires 1', 951-, 20, 1a and 28, back to transformer r it follows, that if relays B B1 and K are'de-energized and relr K is encrgized, relay P will close. Q ar r'epeate relays 1 1. P and P controlled over analogous circuits.

As shown in the drawing one end of eachsection is provided with a source of track circuit current whiclris normally connected with the rails of the secsion; Referring particularly to section e o, transformer T ha its secondary 7 constantly connected. with the rails adjacent the eft hand end of this section and its primary winding 8 is provided with a circiiiit which passes from transformer H through wires 108 and 114, back contact of relay K wire 116, primary winding 8 of transformer T and wires 2? and 28, back to transformer H It is evident therefore that track circuit curis supplied to section l3-C from trans-v former only when relay K is de-ener- The track transformers T T, T and T controlled in exactly the same manner as track again to section B-C second track trans-- former T is located at the righthand end of this section and is provided *ith a circuit which passes from transformer H through wires 11 and 117, front contact 118 of relay Pt, wire 110, primary winding 8 of track transformer T*, and wires 94 and 1 1 back to transformer H Since relay is energized only when relay K is energized, it follows that track circuit current is supplied to section BC by transformer T only when relay K is energized, and that at such time transformer T is not suppiled with current. Tranforrner T, T", T and T are controlled over circuits similar to the one described for transformer T The track winding 15 of each track relay it 1%, R and R is constantly connected with the rails adjacent one end of its associated section. Referring particularly to section BC, an impedance 11'?' is interposed hetw'een one rail 1 of the section and winding}; 15 of the relay R but means ,are provided for at times shunting this impedance. Thus a path is provided v ch passes from one side of impedance 117, through wire 119, front contact 120 of relay K and wire 118 back to the other side in'ipedance 117. The purpose of this impedance to limit the current through the relay when the track transformer at the same end of the section, as T is energized. The shunt path just traced is carried over a front contact on relay K and we have just found that when relay K is ener 'ized, track transformer T is de-cntransformer T Referring ergized and track transformer T is energised; therefore the inipeoance 11! is sount ed only when the track circuit is being fed from the opposite end of the secti in which case the current leakage through the section reduces the voltage at the relay to such value that it can safely be applied to the relay without series impedance. The remaining end of each section is provided with a track relay which is at times entirely disconnected froin the tracl: Thus the winding of track rcla R is included in a circuit wl ich passes from one rail 1 of the section through wire 119, winding of tra a relay R wi 1J4 back con tact 121, of relay P" and wire 122 hacl: to track rail 1 of section BC. It is clear that the energization of relay will completely disconnect relay ll from section and that this connection will not he re-estahlished till relay P again becomes (lechergiZe-d. Circuits are provided for rela s R and R similar to that just described r controlling relay R Eachof the signals 5 is controlled by '1 associated relays V] and as follows: ferring particularly to signal S the stop or red lanip l of this sie'nal is pro ded w th circuit which passes from the sec lighting transformer J constantly supplied with site?" current from transformer H through wire 123,

c .126, lani'p back contact of relay G wir l of signal S and wire 12? hack to transforiner J This circuit is closedonly wh n relay G is (lo-energized, which is the normal condition of the apparatus corresponding to tile unoccupied condition of track, circuit D and also the track circuit to the right of E and in which case lainp l is lightd so that signal S displays a stop indication. The caution circuit for signal S passes from transformer J through wire 123, front contact 125 or relay G wire 128, reverse contact 129 of relay 1V wire 130, lamp 5 of signal S and wire 12'? back to t 'ansforiner J This circuit closed only when relay G is energized and relay V. is energized by current of reverse relative larity, under which conditions lamp 5 lighted and signal S displays a caution ndication. The proceed circuit for this sic passes from transformer J through 123, front contact 125 of relay G wire norinal contact 129 of relay i wire lamp 6 of signal S and wire 12'? bac. transformer J This circuit is closed only when relay G is energized and relay ll is energized by current or nornial relative po- ,lariwty under which conditions lamp 6 is ghted and signal S dication.

Means are also provided for each section for supplying to the rails in parallel a cur rent which I shall hereafter term a local curdisplays a proceed inw re 138, front contact 139 of relay il wires 1 10 and 14-1 to impedance 132 of secion B-C, thence through the rails of the ection to impedance 133, then through Wire 4:, back contact 1 13 of relay P wire 14%, ficl; contact of relay K wire 1%, front ontact 14;? of relay w, and wire l i-3, back o transformer N This circuit is closed only when revs K and P are Clo-energized and relay 1 s 6 is energized, under which conled with alternating local current of what 11 normal relative polarity. If, er, section AB is occupied by a elay Ti is de-energizet and the local err 111? then passes from secondary 135 of w transfori'ner N through wire 133,

contact of relay 1V, wire 1&5, bacl: iontact 14:5 of relay l wire 1 H, back conact 1 13 of relay P, wire 1 1-2, impedance,

in section BC, through rails of the ction to impedance 13%, thence by wire 180, out contact 181 of relay K wire back contact 147 of relay ll and wir 1418, back to secondary 136 of transformer N This circuit is closed only when relays K P and W are all de-enerq'ized and relay K is on ergized under which conditions the rails of section 13-4] are supplied with local current of what I shall terni reverse relative polarity between impedances 133 and 13 1, but with no local current between iinpedances 132 and 13 1.

Traiiic inovlng from right to left through former N through wire 12%, front contact relay G wire 152, normal contact 151 of 1.53 of relay W wires 154, 15-5 and 15-3, inipedance 133 in section (L4), through the ls of the section to l11'l1)%l1(3 3 132, thence .nrough wire 157, front contact of relay relay P K wire 159, front contact 160, or

tions the rails of section BJC are supill il /Ii wire 161, normal contact 162 of relay ll, wire 163, front contact 16% of relay G and wire 165 back to winding 137 of local transformer N This circuit is closed only when relay ii is energized in the normal direc tion and relays K", P and G are all energized, under which condition local current of normal relative polarity is supplied to the rails of section (1-D between impedance 132 and 133. l-Jhen relay W is energized by current of reverse relative polarity the reversal of contacts and 162 connects wire 155 to wire 163 and wire 161 to wire 152, thus reversing the relative polarity of the local current supplied to section C D. If relay W is de-energized due to traffic conditions in advance such as the presence of a train in section DE or the section to the right of E, relay G will also be de-energized and the local circuit for this section then starts with secondary 13"? and leads through wire 124, back contact 151 of relay G wires 166 and 161, front contact 160 of relay P wire 159, front contact 153 of relay K wire 157, impedance 132 in section CD, thence tiiough the rails of the section to impedance 135, then by wire 167, back contact 16% of relay G and wire 165, back to secondary 137 local transformer N This circuit is closed only when relays K and P are energized and relay G is (lo-energized under which condition the rails of section GD are supplied with'local current of reverse relative polarity bet-ween impedances 132 and 135, but with no local current from impedance 135 to impedance 133.

Traffic moving from right to left through section A-l3 and the section-to the right of E is governed by local circuits similar to those just described for traffic from left to right through section 0-1).

The local circuits for section DE and the section to the left of A are identical with those already traced for section B-G, with the exception that the pole changing or reversing of the relative polarity of the local current is accomplished here by means of a relay G whereas in section B C this operation is controlled by the line relay W.

Before explaining the operation of the system as a whole it should be pointed out that the trackway apparatus herein disclosed is suitable for co-operation with train-carried governing means in the following manner: vi hen the train is on a portion of track which is supplied with track circuit current and local current of normal relative polarity, the gOVQYlllZlP mechanism allows the train to proceed at any rate not in excess of a high speed such as 65 miles per hour; if the tram cbcupies a stretch of track which is supplied with tracl; circuit current and local current, the relative polarity of either of which currents is reversed, the governing mechanism prevents the train from proceeding at speeds in excess of an intermediate speed, such as" 35 miles perhour; and if the train enters a stretch of track to which the supply of either local or track circuit current is for any reason discontinued, the governing mechanism imposes a low speed limitation upon the train whereby the train is prevented from exceedingsome low speed as 15 miles per hour.

in at least one form of train governing apparatus suggested for this purpose the governing mechanism is controlled by the current or currents in the track rails through the medium of receiving appliances carried on the front of the locomotive. It is evidentthat with apparatus of this character the source of track circuit current must at all times be connected withthe rails in advance of the train or the wheels and, axles of the train will shunt the track circuit current away from the receiving apparatus and impose the low speed limitation. The track 'ransformers are so arranged, as willbe seen hereinafter, that all track circuits are fed by transformers connected in advance of a train, irrespective of the direction of traffic. As shown in the drawing, the parts all occupy the positions corresponding to normal condition, that is, the entire stretch of track is unoccupied and each signal S displays a stop indication. I willnow assume that a train moving from right to left enters the stretch of track shown in the drawing. The presence of this train in the portion of track to the right of E has deenergized Vi so that when the train enters the section immediately to the rightof E, thus de-energizing the track relays R associated with this section, the closing of back contact 71 does not energize relay G" but does energize relays G and G Relay G is not energized because its circuit is opened by the de-energization of relay which resulted from the opening ofthefront contacts of relay R The front contacts of relays G and G now close the circuits for lamps 6 of signals S ands", which signals therefore display proceed indications to the, train. 7 I

As the train enters section D-E the closingof a back contact of relay R completes the circuit for relay K which thereupon becomes energized. The circuit is'then complete for relay P since relay B is also deenergizechand relay P therefore picks up, The train new supplied with track circuit current from' transformer T transformer T is de-energized, and the shunt path around impedance 117 at relay R is closed. Local current of normal relative polarity is supplied to the rails of the section from transformer N over the front contacts of relay G The train is therefore-allowed to move at high speed through section DE. If section CD is occupied by another train, however, relay VV will be deenergized, relay G will accordingly be de-ener gized, and signal S will display a stop signali This has no effect upon the supply of track circuitcu-rrent to section DE, but local current of reverse relative polarity now supplied o-this' section between impedances 13 i and and no local current is supplied to the section between impedances 132 and 134-. Tt follows therefore that the train entering section DE at E can proceed at speeds below 35 miles per hour as far as impedance 13+: where its speed is further reduced to 15 miles per hour.

if section CD is unoccupied but section B-C isoccunied the consec uent de-ener ization of relay W reverses the polarity of the current supplied to relay which thereupon closes its reverse contacts, thus causing lamp 50f signal S to be energized and the signal to display a caution indication. The local circuits for section DE iowever are the same as when the track in advance-is unoccupied as described above.

I will now assume that the track to the left of point D isunoccupied, and that a train proceeds from section D-E into section CD. Signal S immediately displays a stop indication due-to the de-energization of track relays R and R whose front contacts control the circuit for relay W The entrance of the train into the section does not affect the track transformers, the track circuit current still being supplied from transformers T Local current of normal relative polarity is also supplied to the rails ofthe section throughout their length from local transformer N over front contacts of relay associated with the sec tion 3-4]. The train is therefore permitted to pass through section CD at high spoed.= If section BC is occupied, relay W is dc-energized so that its back contact is closed, and this causes the local current between impedances 13% and 133 in seotion @D to be reversed thus imposing an intermediate speed limitation through this portion of track, and causes the local current to be completely discontinued between the impedances 1 32 and 184, thus imposing a low speed limitation upon the train through this portion of track.

Itshould alsobe pointed out'that the entrance of the train into section CD causes the d-e-energizat-ion of the opposing line relay W Since-relay K is Clo-energized, the opening of front contact 17 of relay W deenergizes relay W The opening of front contact 168 of relay opens, in turn, the circuit for relay W which thereupon be comes 'de-energized. A train moving from left to right through the section to the left of A cannot pick up relay G and therefore cannot clear signal S, which feature prevents the possibility of a head-on collision between. points A and D. It is obvious from the clrawingtliat similar protection is at forded for trafiic in the opposite direction, should a train moving from left to right pass point A when the portion of track be tween points A and D is occupied.

As the train moving from right to left enters section Al3 at point B, the two track relays R and R will become de-energized. The closing of the back contacts of relay It connects primary 8 of transforntier With a source of energy and track c "cuit current is therefore supplied to the rails of the section by this transformer. The closing of the back contacts of relay it onegizes relay K which in turn piclrs up relay P. At the same time, the opening of a front contact of traclr relay R rile-energizes relay N which opens its front contacts and closes its back contacts. A front contact of relay K, which relay is now one; i closes a shunt around impedance 11'5" mally in series with winding 15 of relay Relay W is de-energized, its circuithaving been interrupted by the opening of a front contact of relay 1%. Consequently, the closing of back contact 71 of relay l3 does not pickup relay G but relay G is picked up, as are also the similar relays located at the other end of the passing Sl(lll3,,' F but not shown in the drawing; The opera tion of these relays is, however, the same as that of the similar relays G at siding F and itis therefore apparent that the polarity of the current supplied to relay 3V will'bc rcversed and the armatures of this relay will swing to the right, closing the normal con tacts controlled thereby. The circuit for lamp 6 of signal S is now complete and the signal accordingly displays a proceed indication.

It should be borne in mind that the larity of the current supplied to relay is controlled by a relay not shown in the drawing, in the same manner that the polarity of current supplied to relay li is controlled by relay G It will therefore be clear that when the block to the left of point A is unoccupied, the entrance the train moving from right to left i LO section AB, by causing; the pick-up of the G relays at sidingl will cause relay W to be energized in the norms direction. If the section immediately to the of point A is occupied, relay V1 and also relay will be de-energized, whereas if an opposing train occupies a portion of the lock to the left of point A. more remote than the first. section, that is, the section immediately to the left of A, relay is energized in the reverse direction. In this latter case signal S is at caution and local current of reverse relative polarity is supplied to the rails of section AB throughout their length from transformer N A train moving' through this section from right to left ill llO

is therefore held below 35 miles per hour. if relay V3 is energized in the normal direction, lamp 6 of signal S is energized, whereupon this signal displays a proceed indication. Simultaneously, local current of normal relative polarity is suppliedto the rails of the section AB throughout their length. If the section to the left of A is ccupied however, the consequent dc-energization of relays Vs and G causes lamp a of signal S to be energized, thus displaying a stop indication, and causes local current of reverse relative polarity to be supplied to section A-B between i1nped ances 13 i and 133; but no local current will be supplied to the rails of this section between impedances 132 and A train moving through section AB under these conditions will be allowed to proceed at 35 miles per hour as far as point 13d but will be enabled to proceed past that point only at speeds below 15 miles per hour.

1 will now assume that a train moving from left to right enters section AB and stops. As explained above all the opposing line relays W, VP and W will be ole-energized. If a train moving from right to left enters section CD at point D it is immediately reduced to slow speed even though it is supplies with track circuit current from transformer T because the local circuit for this section is now broken at front contact 170 of auxiliary relay K If this train proceeds, at slow speed, through section C-D and enters section BG, relay K is not energized because the pickup circuit for this relay is broken at front contact 91 of line relay ll which is still de-energized. Relay 7 is of course de-energized and relay K cannot pickup. No local current is supplied to section B C and the speed of the train is thus held to 15 miles per hour throughout the portion of track shown in the drawing. A following train is sul jected to the same speed restrictions for the same reasons, for under no conditions can local current be supplied to the section when the associated relay. W is de-energized prior to the entrance into the section of a train moving in the direction in which. that relay governs.

If, however, the portion of track shown in the drawing is unoccupied and a. train moving from right to left passes into section l" -C at point C, the de-energization of line relay lV and the energization of relay K closes a local circuit for section C-D which allows normal operation of a following train, that is, a following train is reduced to 35 miles per hour at point D, and to 15 miles per hour at impedance 13a in section C-D.

Elie operation of the apparatus as a train proceeds from left to right through the portion of track shown in the drawing will be readily understood from the foregoing clescription of the operation of the apparatus when a train moves through the stretch from right to left.

lit should be particularly noted that a points 13 and C the circuits for the auxiliary relays K are such that they will not be picked up unless theopposing line relay V1 is in the proper position, that is, de-enen gized. vents energization of the relays K should the associated line relay stick in its energized position.

Although I have herein shown and described only one form and arrangement of railway controlling apparatus embodying my invention, it is understood that various cl anges and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. Railway controlling apparatus comprising a section of railway track, a track relay for said section, a line relay for said section controlled in partby the associated track relay, an auxiliary relay controlled in part by said track and line relays and in part by traiiic conditions beyond section, and a signal for said section controlled by the associated line relay and auxiliary relay.

2. Railway traffic controlling apparatus comprising two sections of railway track, a track relay for each section, a line relay for each section controlled in part by the associated track relay, a normally ole-energized auxiliary relay associated with each line relay, and a circuit for each said auxiliary relay controlled by the associated line relay and including in parallel two back contacts one on each said track relays.

3. In combination a portion of railway track comprising a forward, a middle and a rear section, a track relay for each end of said middle sect-ion, a track relay for said forward section, a track relay for said rear section, a line relay associated with each track relay, a normally ole-energized auxiliary relay associated with each line relay,

and means for simultaneously energizing two of said auxiliary relays when a train occupies the forward section and for simultaneously energizing the remaining auXiliary relays when a train occupies the rear section.

4. In combination, a forward, a middle and and a rear section of railway track, a track relay for each end of said middle section, a track'relay for said forward section,

a track relay for said rear section, a line relay associated with each track relay, a nor mally tie-energized auxiliary relay associated with each line relay, means for connecting one terminal of each of the said This is of importance since it pro auxiliary relays to a common point, four hack contacts one on each said track relay interpcsec in parallel between said con men poin id one term nal an energy source d by the assoc ated line i r ternrinal of r each end of ii i: Sfllfl nnddle section, a track relay for said 7 J! 1 1 =1 21 2 lo ioi sale real le-energized auxilr ed w th each 1 forward, a middle relay for each end of sai it. B s

track relay for said forward sect on,

relay for said rear section, a line rele iet track relay, a no "ary reley ass ciate o d a circuit 101- c icinga source o on. each track rela ssociate-d line relay. ration, a forward, a middle ion of railway erd of said in dell i said foruare d rear section with each treclr r ,.l'lZOCl auxiliary relay ESJO i ne relay, and c. circuit for ry relay including is source 1 contact on each track reand a reve pe contacton relay connected in parlv Y Li arch, z

c oud itio re 4 i t said line relay, and :1 local 'ir-cuit a source or energy, a her contact ti said line relay, a front cents. it of said stick relay, and the rails of a portionor s; id

second section.

10. In combination, t successive se time of "ailway track, a line relay for the first seemeresponsive to reversals of rely of current, means controlled section "for supplying said line relay with current of ne relative polarity or the other, a norn'ially de-energize l repeaterrelay for the first section, means controlled by a train the thid section for energizing said re-- w l i l peater relay ea d nne lelay 1s energ zed second section responsive to reversals of r-elith current ofone according as st and second; first and secfor the first: and by said first and? G ectively. three successive sec- 3 lr, a hne relay for the s mi ve to reversals. of relpolarity rrent, means controlled; i n advance of" the first re con said line relay with e polarity or the other, inally de-energrizel repeater relay for rst sect-ion, nesns CODbTOllGC l: by strain; e third section for energizing said ,ater relay it said line relay is'energized in direction, line relay for the second,

tv current, means for supplying; liie relay With current of one 7 clarity or the other according; as ,ter relay is energized; or de-enerrelays to f t and second 1' i c and second t r relay for said n for energizing;

s? relay if said second line ely is energized ineithe? direction, a si r the first section controlled by tail Zoe re ay one said first'repeater seeone line relay and tccoir repeater relay.

1?. ln combination, a stretch of railway raclz, means for atllll'llGS' supplying train controlling current to the rails of said with trathc conditions,

stretch in accoiuan w ich current tl WS through the two rails of he stretch in multiple, and means for disoply when the stretch is ly cc pied by two trains rnovopposite dire vions.

18. Yin con'ihinati n, a stretch of railway track, a track cii: nit for said stretch, means effective when train enters such stretch to supply local train controlling current to the rails of the section in multiple providc conditions in advance of; the first 1 it cu ent, means for supplysection responsive to reversals of relative.

n either direction, a line relay for they fo salt second. section ed the stretch is not occupied by an opposing train.

14. In combination, a stretch of railway track, means-for supplying said stretch with local train controlling current when the stretch is occupied by trains moving in the same directions, which current flows through the two rails of the stretch in multiple, and l V 7 In testimony whereof I afiix my signature.

HERBERT A. WALLACE. 

